1. Field of the Invention
The present invention relates to an organic light-emitting display device. More particularly, the invention relates to an organic light-emitting display device encapsulated with a frit to prevent an infiltration of oxygen and moisture thereinto.
2. Description of the Related Art
In general, an organic light-emitting display device comprises a first substrate comprising a pixel region and a non-pixel region, and a second substrate opposed and disposed to the first substrate and bonded to the first substrate with sealant such as epoxy for encapsulation.
In the pixel region of the first substrate, a plurality of organic light-emitting diodes are formed at intersecting portions of scan lines and data lines in the form of a matrix. Each organic light-emitting diode comprises i) an anode electrode, ii) a cathode electrode and iii) an organic thin film layer. The organic thin film layer may comprise a hole transporting layer, the cathode electrode, a light-emitting layer, and an electron transporting layer. The thin film layer may be formed between the anode electrode and the cathode electrode.
Since the organic light-emitting diode includes organic material, it is vulnerable to degradation in the presence of oxygen. Further, since the cathode electrode is made of a metal material, it may be oxidized by moisture in the air so as to degrade its electrical and light-emitting characteristics. To prevent this, a moisture absorbent material is mounted on a container, e.g., manufactured in the form of a can or cup made of metal material, or on a second substrate of organic, plastic, etc., in the form of powder, or adhered thereto in the form of a film, thereby removing moisture penetrating from the surroundings.
However, the method of mounting the moisture absorbent material in the form of powder can cause problems such as complicating the process, increasing material and process costs, increasing the thickness of a display device, and being difficult to apply to a front light-emitting display configuration. Also, the method of adhering moisture absorbent material in the form of a film can cause problems in that it is limited in its ability to remove moisture and it is difficult to apply to mass production due to low durability and reliability.
Therefore, in order to solve such problems, there has been proposed a method of encapsulating a light-emitting element by forming a sidewall with a frit.
U.S. patent Ser. No. 10/414,794 (Apr. 16, 2003) discloses a glass package encapsulated by adhering a first glass plate and a second glass plate with a frit and method of manufacturing the same.